Anti-seismic test device for steel structure connection node

Abstract

The invention relates to the technical field of detection devices, in particular to an anti-seismic test device for a steel structure connection node. An anti-seismic test device for a steel structure connection node comprises two adjusting mechanisms. The adjusting mechanism comprises a rotating shaft, an eccentric assembly and an adjusting assembly. The eccentric assembly comprises a plurality of eccentric wheels. The plurality of eccentric wheels are divided into a plurality of first wheels and a plurality of second wheels. The two rotating shafts rotate in the same direction, and the first wheel or the second wheel drives the movable platform to reciprocate through the adjusting assembly. The sum of the eccentric forces of the first wheels on one rotating shaft is equal to the sum of the eccentric forces of the second wheels, and the eccentric directions of the first wheels and the second wheels are opposite, so that the rotating shaft can be prevented from vibrating up and down by the first wheels and the second wheels. The invention provides an anti-seismic test device for a steel structure connection node, and aims to solve the problem that when an eccentric cam structure is used in an existing anti-seismic test device, a cam shaft vibrates up and down due to eccentricity of a cam, so that an anti-seismic test is affected.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of detection devices, in particular to an anti-seismic testing device for steel structure connecting nodes. BACKGROUND

[0002] The anti-seismic testing device for steel structure connecting nodes is a key equipment for simulating earthquake action in a laboratory environment and evaluating the anti-seismic performance of nodes. Its core function is to test the performance of nodes under strong earthquakes by precisely applying simulated earthquake loads, providing a scientific basis for structural safety.

[0003] Steel structures are widely used in modern buildings, especially high-rise and large-span structures in earthquake-prone areas, due to their high strength, light weight, and good ductility. Numerous seismic damage investigations (such as the 1994 Northridge earthquake in the United States and the 1995 Kobe earthquake in Japan) have shown that the destruction of steel structure buildings often does not occur in beam or column components, but in the beam-column connecting node area. Node failure can cause the overall collapse of the structure. Therefore, the connecting node is a key part of ensuring the overall seismic performance of the steel structure, and its strength, stiffness, ductility, and energy dissipation capacity under earthquake action directly affect the safety of the structure.

[0004] Traditional testing devices are mainly divided into two categories: electro-hydraulic servo actuator systems and mechanical excitation systems. The electro-hydraulic servo actuator system uses a high-power servo actuator to achieve vibration, but this device has high costs and high energy consumption. The mechanical excitation system uses the centrifugal force generated by the rotation of the eccentric wheel to make the test piece vibrate, but the amplitude (intensity of vibration) of the mechanical excitation system is usually fixed and determined by the eccentricity of the eccentric wheel. If you want to change the amplitude, you must stop the machine and manually replace the eccentric wheel with a different eccentricity, or make complex mechanical adjustments. This process is very time-consuming and labor-intensive, severely affecting the testing efficiency.

[0005] The utility model patent with publication number CN220708671U provides a structural anti-seismic test device. The device sets up a first bearing to support a threaded rod, uses a second sliding groove to guide a second fixed block, and sets up a second opening and a second bearing to facilitate the installation and operation of a cam and a rotating rod, aiming to solve the problem of existing devices that cannot simulate multiple vibration modes and the test piece is not fixed firmly. However, when using the eccentric cam structure, the device will cause the shaft to vibrate up and down due to its inherent eccentricity. Such additional vibration interference will have a negative impact on the accurate simulation of node performance under earthquake action. SUMMARY

[0006] This invention provides a seismic testing device for steel structure connection nodes to solve the problems of existing seismic testing devices, such as difficulty in amplitude adjustment and the impact on seismic testing caused by the eccentricity of the cam shaft due to eccentricity when using an eccentric cam structure.

[0007] The seismic testing device for steel structure connection nodes of the present invention adopts the following technical solution: A seismic testing device for steel structure connection nodes, used for testing steel structures, includes an installation platform, a movable platform, and two adjustment mechanisms. The movable platform is slidably mounted on the installation platform along a first direction, which is a horizontal direction. The steel structure includes interconnected horizontal and vertical rods, with the horizontal rods fixedly connected to the installation platform. The vertical rods are fixedly connected to the movable platform.

[0008] Two adjustment mechanisms are located on opposite sides of the movable platform along a first direction. Each adjustment mechanism includes a rotating shaft, two eccentric components, and two adjustment components. The rotating shaft is positioned along a second direction and rotatably mounted on the mounting platform. The second direction is horizontal and perpendicular to the first direction.

[0009] Two eccentric components are distributed along a second direction. Each eccentric component includes multiple eccentric wheels distributed along the second direction and eccentrically mounted on a rotating shaft. The eccentricity of the multiple eccentric wheels gradually increases from one end of each eccentric component towards the center of the rotating shaft. The multiple eccentric wheels in each eccentric component are divided into multiple first wheels and multiple second wheels. The eccentric directions of the first wheels and the second wheels are opposite. The sum of the eccentric forces of the multiple first wheels on a rotating shaft is equal to the sum of the eccentric forces of the multiple second wheels.

[0010] During operation, each adjusting component corresponds to one eccentric wheel in an eccentric component. When the two shafts rotate in the same direction, the eccentric wheel in each eccentric component drives the movable platform to reciprocate along the first direction through the adjusting component.

[0011] Furthermore, in the two eccentric components on the same rotating shaft, multiple first wheels correspond one-to-one, and multiple second wheels correspond one-to-one. The eccentricity of two corresponding first wheels is the same, and the eccentricity of two corresponding second wheels is the same. The first wheels with the same eccentricity on the two rotating shafts correspond one-to-one, and the second wheels with the same eccentricity correspond one-to-one.

[0012] Furthermore, each adjustment mechanism includes a bidirectional screw arranged along the second direction, rotatably mounted on the mounting platform. The bidirectional screw has threaded grooves in opposite directions. Each adjustment component includes a slider slidably mounted on the bidirectional screw along the second direction, with each slider corresponding to and threadedly engaging a threaded groove on the bidirectional screw. Each slider abuts against either a first wheel or a second wheel.

[0013] When the bidirectional screw rotates forward, the two sliders on the same bidirectional screw move towards each other. When the bidirectional screw rotates reversely, the two sliders on the same bidirectional screw move away from each other.

[0014] Further, each slider is provided with a flat surface and an inclined surface at one end close to the eccentric wheel. The directions of the inclined surfaces on the two sliders on the same shaft are opposite. When the eccentric farthest point of the first wheel on one shaft contacts the corresponding slider, the corresponding two sliders on the other shaft move away from each other, so that there is a gap between the eccentric closest point of the first wheel on the other shaft and the inclined surface on the corresponding slider, for reducing the friction between the first wheel and the slider.

[0015] Further, the mounting platform comprises a base and two supports, and the base and the supports are fixed to the ground. The two supports are vertically arranged on both sides of the base along the first direction. The movable platform is slidingly arranged on the base along the first direction. The horizontal rod is arranged along the first direction, and the two ends of the horizontal rod are fixedly connected with the two supports, respectively.

[0016] Further, each adjusting mechanism comprises at least one transmission assembly, and the transmission assembly comprises a rack and a pinion. The rack is fixedly arranged on the mounting platform and arranged along the first direction. The pinion is fixedly arranged on the bidirectional screw and coaxially arranged with the bidirectional screw.

[0017] When the center of the movable platform and the centers of symmetry of the two adjusting mechanisms are on the same vertical line, the pinion and the rack are disengaged. When the center of the movable platform deviates from the centers of symmetry of the two adjusting mechanisms, the pinion and the rack in the adjusting mechanism close to the movable platform are engaged.

[0018] When the movable platform moves towards one shaft, the pinion and the rack in the adjusting mechanism of the shaft are engaged, and then the pinion reversely rotates and the bidirectional screw reversely rotates. When the movable platform moves away from one shaft, the pinion in the adjusting mechanism of the shaft reversely rotates and the bidirectional screw reversely rotates.

[0019] Further, a hand wheel is fixedly arranged on each bidirectional screw, and rotating the hand wheel is used to drive the bidirectional screw to rotate.

[0020] Further, each adjusting mechanism comprises at least one driving assembly, and the driving assembly comprises a motor, a first transmission wheel and a belt. The motor is fixedly arranged on the base. The first transmission wheel is fixedly arranged on the shaft and coaxially arranged with the shaft. The belt connects the output shaft of the motor and the first transmission wheel.

[0021] Further, each eccentric wheel comprises an inner wheel, an outer wheel and a plurality of balls. The inner wheel is fixedly connected with the shaft and eccentrically arranged with the shaft. The outer wheel is rotatably arranged outside the inner wheel and coaxially arranged with the inner wheel. The plurality of balls are arranged between the inner wheel and the outer wheel.

[0022] Further, the base is fixedly provided with a guide rail along the first direction, and the lower side of the movable platform is provided with a sliding groove along the first direction, and the guide rail and the sliding groove are in sliding cooperation.

[0023] The beneficial effects of the present application are that: the adjusting mechanism is provided, and the eccentric distances of the plurality of eccentric wheels in each eccentric assembly are different, so that the plurality of eccentric wheels move different distances along the first direction by the adjusting assembly. According to the amplitude of the vibration caused by the rotation of the eccentric wheel required for each detection, the corresponding first wheel or second wheel is selected to correspond to the adjusting assembly. The plurality of eccentric wheels are provided, so that the amplitude of the steel structure connecting joint seismic test device is adjustable, and the working efficiency is higher.

[0024] The two rotating shafts rotate in the same direction. The first wheel or the second wheel in each eccentric assembly drives the movable platform to move back and forth along the first direction through the adjusting assembly. The movable platform drives the vertical rod to move, thereby testing the steel structure.

[0025] Since the sum of the eccentric forces of the plurality of first wheels on one rotating shaft is equal to the sum of the eccentric forces of the plurality of second wheels, and the eccentric directions of the first wheel and the second wheel are opposite. Therefore, during the rotation of the rotating shaft, the eccentric force of the plurality of first wheels on the rotating shaft and the eccentric force of the plurality of second wheels on the rotating shaft are the same in size and opposite in direction, and they cancel each other out. Avoiding the axial center of the first wheel and the second wheel deviating from the rotating shaft axis, the first wheel and the second wheel in the rotating process cause the up and down vibration of the rotating shaft, thereby affecting the seismic test of the steel structure. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0027] Figure 1 A structural schematic view of a steel structure connecting joint seismic test device provided by the embodiment of the present application; Figure 2 A side view of a steel structure connecting joint seismic test device provided by the embodiment of the present application; Figure 3 A Figure 2 A sectional view in the direction of A-A; Figure 4 A Figure 3 An enlarged view of C; Figure 5 A Figure 2A sectional view along the direction of B-B; Figure 6 A sectional view along the direction of B-B; Figure 5 An enlarged view at D; Figure 7 A top view of an anti-seismic testing device for a steel structure connecting joint provided by an embodiment of the present application; Figure 8 A sectional view along the direction of B-B; Figure 7 An enlarged view at E; Figure 9 A partial structural schematic diagram of an anti-seismic testing device for a steel structure connecting joint provided by an embodiment of the present application; Figure 10 A structural schematic diagram of a base of an anti-seismic testing device for a steel structure connecting joint provided by an embodiment of the present application; Figure 11 A partial structural schematic diagram of an adjusting mechanism of an anti-seismic testing device for a steel structure connecting joint provided by an embodiment of the present application; Figure 12 Another partial structural schematic diagram of an adjusting mechanism of an anti-seismic testing device for a steel structure connecting joint provided by an embodiment of the present application.

[0028] In the figure: 100, base; 101, support column; 102, belt; 103, motor; 105, rack; 106, guide rail; 201, movable platform; 202, sliding block; 2021, flat surface; 2022, inclined surface; 203, bidirectional screw; 204, gear; 205, hand wheel; 301, rotating shaft; 302, first wheel; 3021, ball; 303, second wheel; 304, first transmission wheel; 401, horizontal rod; 402, vertical rod. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the protection scope of the present application.

[0030] Referring to Figures 1 to 12 The anti-seismic testing device for a steel structure connecting joint provided by the embodiment of the present application is used for detecting a steel structure, and includes a mounting platform, a movable platform 201 and two adjusting mechanisms. The movable platform 201 is slidingly arranged on the mounting platform along a first direction, and the first direction is a horizontal direction.

[0031] The steel structure comprises horizontal rods 401 and vertical rods 402 connected with each other, the horizontal rods 401 are fixedly connected with the mounting platform and arranged along a first direction. The vertical rods 402 are arranged vertically, the upper ends of the vertical rods 402 are fixedly connected with the horizontal rods 401, the lower ends of the vertical rods 402 are fixedly connected with the movable platform 201, and the centers of the vertical rods 402 and the center of the movable platform 201 are on the same vertical line.

[0032] The two adjusting mechanisms are respectively located on the two sides of the movable platform 201 along the first direction. Each adjusting mechanism comprises a rotating shaft 301, two eccentric assemblies and two adjusting assemblies. The rotating shaft 301 is arranged along a second direction and rotatably arranged on the mounting platform. The second direction is a horizontal direction and perpendicular to the first direction.

[0033] The two eccentric assemblies are distributed along the second direction, and each eccentric assembly comprises a plurality of eccentric wheels distributed along the second direction and eccentrically arranged on the rotating shaft 301. Along the direction from one end of each eccentric assembly to the center of the rotating shaft 301, the eccentric distances of the plurality of eccentric wheels gradually increase. The plurality of eccentric wheels in each eccentric assembly are divided into a plurality of first wheels 302 and a plurality of second wheels 303. The eccentric directions of the first wheels 302 and the second wheels 303 are opposite. The plurality of first wheels 302 are sequentially distributed along the axial direction of the rotating shaft 301, and the plurality of second wheels 303 are sequentially distributed along the axial direction of the rotating shaft 301. Preferably, the plurality of first wheels 302 and the plurality of second wheels 303 are alternately arranged.

[0034] The sum of the eccentric forces of the plurality of first wheels 302 on one rotating shaft 301 is equal to the sum of the eccentric forces of the plurality of second wheels 303. The eccentric force of the first wheel 302 is the product of the eccentric distance of the first wheel 302 and the mass of the first wheel 302. The eccentric force of the second wheel 303 is the product of the eccentric distance of the second wheel 303 and the mass of the second wheel 303. The eccentric distance is the distance between the shaft center of the eccentric wheel and the shaft center of the rotating shaft 301.

[0035] During operation, each adjusting assembly corresponds to one first wheel 302 or second wheel 303 in one eccentric assembly. When the two rotating shafts 301 rotate in the same direction, the first wheel 302 or the second wheel 303 in each eccentric assembly drives the movable platform 201 to reciprocate along the first direction through the adjusting assembly.

[0036] First, the horizontal rods 401 are fixedly connected with the mounting platform, and the vertical rods 402 are fixedly connected with the middle part of the movable platform 201. In the initial state, the shaft center of the first wheel 302 or the second wheel 303 is on the same straight line as the shaft center of the rotating shaft 301, and the straight line is vertically arranged.

[0037] Since the eccentric distances of the plurality of eccentric wheels in each eccentric assembly are different, the plurality of eccentric wheels push the movable platform 201 to move along the first direction by different distances through the adjusting assemblies. According to the amplitude of the vibration caused by the rotation of the eccentric wheel required at each time of detection, the corresponding first wheel 302 or second wheel 303 is selected with the adjusting assembly. For example, when the adjusting assembly corresponds to the first wheel 302, all other adjusting assemblies also correspond to the first wheel 302, and are the same eccentric distance first wheel 302. When the adjusting assembly corresponds to the second wheel 303, all other adjusting assemblies also correspond to the second wheel 303, and are the same eccentric distance second wheel 303.

[0038] The two rotating shafts 301 rotate in the same direction, and the first wheel 302 or the second wheel 303 in each eccentric assembly drives the movable platform 201 to move reciprocally along the first direction through the adjusting assembly. The movable platform 201 drives the vertical rod 402 to move, thereby testing the steel structure.

[0039] Since the sum of the eccentric forces of the plurality of first wheels 302 on one rotating shaft 301 is equal to the sum of the eccentric forces of the plurality of second wheels 303, and the eccentric directions of the first wheel 302 and the second wheel 303 are opposite. Therefore, during the rotation of the rotating shaft 301, the eccentric force of the plurality of first wheels 302 on the rotating shaft 301 and the eccentric force of the plurality of second wheels 303 on the rotating shaft 301 are the same in size and opposite in direction, and they cancel each other out. Avoiding the up and down vibration of the rotating shaft 301 caused by the center of the first wheel 302 and the second wheel 303 deviating from the axis of the rotating shaft 301 during the rotation of the first wheel 302 and the second wheel 303, thereby affecting the anti-seismic test of the steel structure.

[0040] In the embodiment, the plurality of first wheels 302 in the two eccentric assemblies on the same rotating shaft 301 correspond one-to-one, and the plurality of second wheels 303 correspond one-to-one. The eccentric distances of the corresponding two first wheels 302 are the same, and the eccentric distances of the corresponding two second wheels 303 are the same. The eccentric distances of the first wheels 302 on the two rotating shafts 301 are the same, and the eccentric distances of the second wheels 303 are the same.

[0041] In the embodiment, each adjusting mechanism further includes a bidirectional screw 203 arranged along the second direction, and the bidirectional screw 203 is rotationally arranged on the mounting platform. Each bidirectional screw 203 is between a rotating shaft 301 and the movable platform 201. The bidirectional screw 203 is provided with screw grooves in opposite directions.

[0042] Each adjusting assembly comprises a slider 202, which is slidingly arranged on the bidirectional screw 203 along the second direction, and each slider 202 and a threaded groove on the bidirectional screw 203 correspond and threadedly match. Each slider 202 abuts against a first wheel 302 or a second wheel 303. The types of wheels (the first wheel 302 or the second wheel 303) and the eccentric distances abutted by all sliders 202 are the same.

[0043] When the bidirectional screw 203 rotates forward, the two sliders 202 on the same bidirectional screw 203 move close to each other. When the bidirectional screw 203 rotates reversely, the two sliders 202 on the same bidirectional screw 203 move away from each other.

[0044] In the embodiment, each slider 202 is provided with a flat surface 2021 and an inclined surface 2022 on the end close to the eccentric wheel, and the directions of the inclined surfaces 2022 on the two sliders 202 on the same rotating shaft 301 are opposite. The flat surfaces 2021 and the inclined surfaces 2022 are sequentially distributed along the direction gradually close to the adjacent slider 202. Along the direction gradually close to the adjacent slider 202, the inclined surfaces 2022 gradually close to the movable platform 201. The flat surface 2021 abuts against the slider 202, increasing the stability.

[0045] When the eccentric farthest point of the first wheel 302 on one rotating shaft 301 contacts the corresponding slider 202, at this time, the two sliders 202 corresponding to the other rotating shaft 301 move away from each other, so that the eccentric closest point of the first wheel 302 on the other rotating shaft 301 and the inclined surface 2022 on the corresponding slider 202 have a gap, and the gap is the largest, which is used to reduce the friction between the first wheel 302 and the slider 202.

[0046] In the embodiment, the mounting platform comprises a base 100 and two supports 101, and the base 100 and the supports 101 are fixed to the ground. The two supports 101 are vertically arranged on the two sides of the base 100 along the first direction. The movable platform 201 is slidingly arranged on the base 100 along the first direction. The horizontal rod 401 is arranged along the first direction, and the two ends of the horizontal rod 401 are fixedly connected with the two supports 101, respectively. The material of the horizontal rod 401 can be concrete or steel structure.

[0047] In the embodiment, each adjusting mechanism comprises at least one transmission assembly, and the transmission assembly comprises a rack 105 and a gear 204. The rack 105 is fixedly arranged on the mounting platform, and the rack 105 is arranged along the first direction. The gear 204 is fixedly arranged on the bidirectional screw 203, and is coaxially arranged with the bidirectional screw 203.

[0048] When the center of the movable platform 201 and the centers of symmetry of the two adjusting mechanisms are on the same vertical line, the gear 204 and the rack 105 are disengaged. When the center of the movable platform 201 deviates from the centers of symmetry of the two adjusting mechanisms, the gear 204 and the rack 105 in the adjusting mechanism close to the movable platform 201 are engaged.

[0049] When the movable platform 201 approaches a rotating shaft 301, the gear 204 reversely rotates after the rack 105 and the gear 204 in the adjusting mechanism where the rotating shaft 301 is located are engaged, the bidirectional screw rod 203 reversely rotates, and the two sliding blocks 202 on the bidirectional screw rod 203 move away from each other. When the movable platform 201 moves away from a rotating shaft 301, the gear 204 in the adjusting mechanism where the rotating shaft 301 is located rotates forward, the bidirectional screw rod 203 rotates forward, and the two sliding blocks 202 on the bidirectional screw rod 203 move close to each other.

[0050] In the embodiment, a hand wheel 205 is fixedly arranged on each bidirectional screw rod 203, and rotating the hand wheel 205 is used to drive the bidirectional screw rod 203 to rotate.

[0051] In the embodiment, each adjusting mechanism comprises at least one driving assembly, and the driving assembly comprises a motor 103, a first transmission wheel 304 and a belt 102. The motor 103 is fixedly arranged on the base 100. The first transmission wheel 304 is fixedly arranged on the rotating shaft 301 and coaxially arranged with the rotating shaft 301. The belt 102 connects the output shaft of the motor 103 and the first transmission wheel 304. The motor 103 drives the first transmission wheel 304 to rotate through the first transmission belt, and in turn drives the rotating shaft 301 to rotate.

[0052] In the embodiment, each eccentric wheel comprises an inner wheel, an outer wheel and a plurality of balls 3021. The inner wheel is fixedly connected with the rotating shaft 301 and eccentrically arranged with the rotating shaft 301. The outer wheel is rotatably arranged outside the inner wheel and coaxially arranged with the inner wheel. The plurality of balls 3021 are arranged between the inner wheel and the outer wheel. The inner wheel and the outer wheel can rotate relative to each other, thereby reducing the friction between the eccentric wheel and the sliding block 202.

[0053] In the embodiment, the base 100 is fixedly provided with a guide rail 106 along a first direction, and the lower side of the movable platform 201 is provided with a sliding groove along the first direction. The guide rail 106 and the sliding groove are in sliding fit, so that the movable platform 201 can only move along the first direction.

[0054] Working process: first, the two ends of the horizontal rod 401 are fixedly connected with the two supports 101 respectively. Then, the lower end of the vertical rod 402 is fixedly connected with the middle part of the movable platform 201. In the initial state, the center of the movable platform 201 and the centers of symmetry of the two adjusting mechanisms are on the same vertical line, which is the initial position of the movable platform 201. The rack 105 and the gear 204 are disengaged. In the initial state, the shaft centers of the first wheel 302 or the second wheel 303 are on the same straight line as the shaft center of the rotating shaft 301, and the straight line is vertically arranged. In addition, the eccentric farthest point of the first wheel 302 is higher than the eccentric farthest point of the second wheel 303. The eccentric farthest point of the first wheel 302 is the farthest point of the first wheel 302 from the center of the rotating shaft 301.

[0055] Since the eccentric distances of the plurality of eccentric wheels in each eccentric assembly are different, the distances that the eccentric wheels push the slider 202 and the movable platform 201 to move in the first direction are different. According to the amplitude of the vibration caused by the rotation of the required eccentric wheel each time, the corresponding first wheel 302 or second wheel 303 is selected to abut against the slider 202. The hand wheel 205 is manually rotated, the hand wheel 205 drives the bidirectional screw 203 to rotate, and the bidirectional screw 203 drives the two sliders 202 to move, so that the eccentric distances of the first wheels 302 abutting against all the sliders 202 are the same.

[0056] Then, the motor 103 is started, the motor 103 drives the first transmission wheel 304 to rotate through the first transmission belt, and then drives the rotating shaft 301 to rotate. The two rotating shafts 301 rotate in the same direction, and the rotating shaft 301 drives the first wheel 302 and the second wheel 303 to rotate.

[0057] The two sides of the movable platform 201 along the first direction are a first side and a second side respectively. When the eccentric farthest point of the first wheel 302 on the first side deflects toward the direction close to the movable platform 201, the slider 202 on the first side pushes the movable platform 201 to move in the direction from the first side to the second side. At this time, the eccentric farthest point of the second wheel 303 on the second side deflects away from the movable platform 201 to leave space for the movement of the movable platform 201.

[0058] In the process of the movement of the movable platform 201 from the first side to the second side, the gear 204 on the second side and the rack 105 engage, and drive the bidirectional screw 203 on the second side to rotate in the opposite direction, and the bidirectional screw 203 drives the two sliders 202 on the second side to move away from each other. Since the slider 202 is provided with the inclined surface 2022, after the two sliders 202 move away from each other, the distance between the inclined surface 2022 of the slider 202 and the first wheel 302 gradually increases.

[0059] When the eccentric farthest point of the first wheel 302 on the first side contacts the corresponding slider 202, the movable platform 201 moves to a first limit position along a direction from the first side to the second side. At this time, there is a gap between the inclined surface 2022 on the slider 202 on the second side and the eccentric nearest point of the first wheel 302 on the second side, and the gap is the largest. This prevents the movable platform 201 from interfering between the slider 202 on the second side and the first wheel 302 on the second side when the first wheel 302 on the second side approaches, and at the same time reduces the friction between the first wheel 302 and the slider 202 when the first wheel 302 rotates, thereby prolonging the service life of the first wheel 302. The first limit position is the farthest distance that the first wheel 302 can push the movable platform 201 to move, that is, the moving distance is the eccentricity of the first wheel 302.

[0060] After the first wheel 302 continues to rotate, the eccentric farthest point of the first wheel 302 on the first side deflects away from the movable platform 201, at which time the first wheel 302 on the first side no longer pushes the slider 202. The eccentric farthest point of the first wheel 302 on the second side deflects towards the movable platform 201.

[0061] When the movable platform 201 moves along the first direction, the lower end of the vertical rod 402 is synchronously moved, and the vertical rod 402 gradually tilts. When the first wheel 302 on the first side no longer pushes the slider 202, and there is a gap between the slider 202 on the second side and the first wheel 302, the movable platform 201 is not pushed by any first wheel 302 at this time, at which time the vertical rod 402 will have three situations: The first situation: the vertical rod 402 produces elastic deformation without plastic deformation. After the vertical rod 402 tilts, the vertical rod 402 resets under the action of its own elasticity, the vertical rod 402 drives the movable platform 201 to move along a direction from the second side to the first side and reset until the vertical rod 402 is completely vertical, at which time the vertical rod 402 moves the movable platform 201 to the initial position.

[0062] During the movement of the movable platform 201 from the first limit position to the initial position, the gear 204 on the second side and the rack 105 cooperate with each other to make the bidirectional screw 203 on the second side rotate in a forward direction. The bidirectional screw 203 rotates in the forward direction to drive the two sliders 202 to approach each other to the abutting position of the plane 2021 of the slider 202 and the first wheel 302.

[0063] At this time, the eccentric farthest point of the first wheel 302 on the second side continues to rotate towards the movable platform 201. The first wheel 302 on the second side pushes the movable platform 201 to move along a direction from the second side to the first side to a second limit position through the slider 202. The second limit position is the farthest distance that the first wheel 302 can push the movable platform 201 to move.

[0064] The second case: the vertical rod 402 produces partial plastic deformation, and the vertical rod 402 can drive the movable platform 201 to move a distance along the direction from the second side to the first side. The rack 105 and the gear 204 on the second side are engaged, and the bidirectional screw rod 203 is positively rotated, and the two second side sliders 202 are close to each other. When the inclined surface 2022 of the slider 202 and the first wheel 302 are in contact, under the action of the movement of the movable platform 201 driven by the vertical rod 402 and the movement of the movable platform 201 pushed by the rotation of the first wheel 302, the planes 2021 of the two sliders 202 and the first wheel 302 are in abutment, and the movable platform 201 is moved from the first limit position to the initial position.

[0065] The third case: the vertical rod 402 produces plastic deformation and cannot drive the movable platform 201 to move. At this time, the machine needs to be stopped, the steel structure is disassembled, and the hand wheel 205 is rotated. The rack 105 and the gear 204 are engaged, the gear 204 is rotated, and the movable platform 201 is moved to the initial position.

[0066] The two rotating shafts 301 are continuously rotated, and then the movable platform 201 is driven by the slider 202 to move reciprocatingly along the first direction. Since the sum of the eccentric forces of the plurality of first wheels 302 on one rotating shaft 301 is equal to the sum of the eccentric forces of the plurality of second wheels 303, and the eccentric directions of the first wheel 302 and the second wheel 303 are opposite. Therefore, during the rotation of the rotating shaft 301, the eccentric force of the plurality of first wheels 302 on the rotating shaft 301 and the eccentric force of the plurality of second wheels 303 on the rotating shaft 301 are equal in size and opposite in direction, and they cancel each other out. Avoiding the up and down vibration of the rotating shaft 301 caused by the center of the first wheel 302 and the second wheel 303 deviating from the axis of the rotating shaft 301 during the rotation of the first wheel 302 and the second wheel 303, thereby affecting the anti-seismic test of the steel structure.

[0067] After one detection is completed, the movable platform 201 is moved to the initial position, the rack 105 and the gear 204 are disengaged, and the hand wheel 205 is rotated again to adjust the eccentric wheel contacted by the slider 202, so as to adjust the amplitude during the vibration, thereby performing the next test. The amplitude of the anti-seismic test device of a kind of steel structure connecting joint can be adjusted by setting a plurality of eccentric wheels, and the working efficiency is higher.

[0068] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A seismic testing device for steel structure connection nodes, used for testing steel structures, characterized in that: It includes an installation platform, a movable platform, and two adjustment mechanisms; the movable platform is slidably mounted on the installation platform along a first direction, which is horizontal; the steel structure includes interconnected horizontal and vertical rods, with the horizontal rods fixedly connected to the installation platform; the vertical rods are fixedly connected to the movable platform. Two adjustment mechanisms are located on opposite sides of the movable platform along a first direction; each adjustment mechanism includes a rotating shaft, two eccentric components, and two adjustment components; the rotating shaft is arranged along a second direction and is rotatably mounted on the mounting platform; the second direction is horizontal and perpendicular to the first direction; Two eccentric components are distributed along a second direction. Each eccentric component includes multiple eccentric wheels distributed along the second direction and eccentrically mounted on a rotating shaft. The eccentricity of the multiple eccentric wheels gradually increases from one end of each eccentric component towards the center of the rotating shaft. The multiple eccentric wheels in each eccentric component are divided into multiple first wheels and multiple second wheels. The eccentric directions of the first wheels and the second wheels are opposite. The sum of the eccentric forces of the multiple first wheels on a rotating shaft is equal to the sum of the eccentric forces of the multiple second wheels. During operation, each adjustment component corresponds to one eccentric wheel in an eccentric component; when the two shafts rotate in the same direction, the eccentric wheel in each eccentric component drives the movable platform to reciprocate along the first direction through the adjustment component.

2. The seismic testing device for steel structure connection nodes according to claim 1, characterized in that: Multiple first wheels in two eccentric components on the same rotating shaft correspond one-to-one, and multiple second wheels correspond one-to-one. The eccentricity of two corresponding first wheels is the same, and the eccentricity of two corresponding second wheels is the same. The first wheels with the same eccentricity on two rotating shafts correspond one-to-one, and the second wheels with the same eccentricity correspond one-to-one.

3. The seismic testing device for steel structure connection nodes according to claim 2, characterized in that: Each adjustment mechanism also includes a bidirectional screw arranged along the second direction, which is rotatably mounted on the mounting platform; the bidirectional screw has threaded grooves in opposite directions; each adjustment component includes a slider, which is slidably mounted on the bidirectional screw along the second direction, and each slider corresponds to and is threadedly engaged with a threaded groove on the bidirectional screw; each slider abuts against a first wheel or a second wheel; When the bidirectional screw rotates in the forward direction, the two sliders on the same bidirectional screw move closer to each other; when the bidirectional screw rotates in the reverse direction, the two sliders on the same bidirectional screw move further apart.

4. The seismic testing device for steel structure connection nodes according to claim 3, characterized in that: Each slider has a flat surface and an inclined surface at one end near the eccentric wheel. The inclined surfaces on the two sliders on the same axis are in opposite directions. When the farthest point of the eccentricity of the first wheel on one axis comes into contact with the corresponding slider, the two sliders on the other axis move away from each other, so that there is a gap between the closest point of the eccentricity of the first wheel on the other axis and the inclined surface on the corresponding slider, which is used to reduce the friction between the first wheel and the slider.

5. The seismic testing device for steel structure connection nodes according to claim 3, characterized in that: The installation platform includes a base and two pillars, both of which are fixed to the ground. The two pillars are vertically arranged on both sides of the base along a first direction. The movable platform is slidably arranged on the base along the first direction. A horizontal bar is arranged along the first direction, and its two ends are fixedly connected to the two pillars respectively.

6. The seismic testing device for steel structure connection nodes according to claim 5, characterized in that: Each adjustment mechanism includes at least one transmission component, which includes a rack and a gear; the rack is fixedly mounted on the mounting platform and is arranged along a first direction; the gear is fixedly mounted on a double-acting screw and is coaxial with the double-acting screw. When the center of the movable platform and the center of symmetry of the two adjustment mechanisms are on the same vertical line, the gear and rack disengage; when the center of the movable platform deviates from the center of symmetry of the two adjustment mechanisms, the gear and rack in the adjustment mechanism that the movable platform is closest to engage. When the moving platform moves closer to a rotating shaft, the rack and gear in the adjustment mechanism of that rotating shaft mesh, causing the gear to rotate in the opposite direction and the bidirectional screw to rotate in the opposite direction; when the moving platform moves away from a rotating shaft, the gear in the adjustment mechanism of that rotating shaft rotates in the forward direction and the bidirectional screw rotates in the forward direction.

7. The seismic testing device for steel structure connection nodes according to claim 3, characterized in that: Each bidirectional screw is fixedly equipped with a handwheel, and turning the handwheel drives the bidirectional screw to rotate.

8. The seismic testing device for steel structure connection nodes according to claim 5, characterized in that: Each adjustment mechanism includes at least one drive component, which includes a motor, a first transmission wheel, and a belt; the motor is fixedly mounted on the base; the first transmission wheel is fixedly mounted on the rotating shaft and is coaxial with the rotating shaft; the belt connects the output shaft of the motor to the first transmission wheel.

9. The seismic testing device for steel structure connection nodes according to claim 3, characterized in that: Each eccentric wheel includes an inner wheel, an outer wheel, and multiple balls; the inner wheel is fixedly connected to the shaft and is eccentrically positioned with respect to the shaft; the outer wheel is rotatably positioned outside the inner wheel and is coaxial with the inner wheel; the multiple balls are positioned between the inner wheel and the outer wheel.

10. The seismic testing device for steel structure connection nodes according to claim 5, characterized in that: A guide rail along the first direction is fixedly installed on the base, and a slide groove along the first direction is opened on the lower side of the movable platform. The guide rail and the slide groove slide together.

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